checking amps at stinger

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is there a way to check how many amps i'm getting at the stinger? after several connections, ( at machine, cam locks, ) how can you be certain you don't have bad connection? or can you go by ocv at stinger/ ground clamp?thanks, just some late night wondering.dave
Reply:Cant go by OCV, as that has no relation to anything that happens after the arc is established.Why do you want to check the amps in the first place?  What makes you think there is a problem?Have we all gone mad?
Reply:i use an ac/dc amp clamp next to the work clampDynasty 200DXPassport plus w/ spoolmate 100victor 315c oxy/(act and prop)Miller digital elitemilwaukee power tools
Reply:snoboarder - no problem , just curioushave an old lincoln sa 200, just curious what amps it makes in relation as to what range selector/ rheostat is set on. dave
Reply:A nice clamp on ammeter is handy to have around anyway. AC/DC makes it nice because it's dual use. You always feel a bit guilty because they don't normally get used a lot but when you need one they are handy as heck. They'll all have a hold feature so you wouldn't actually have to be looking at the meter to get your reading. Have it around your stinger lead, get a nice stable arc going the way you'd like it to be, hit the hold button, then take look."The things that will destroy America are prosperity at any price, peace at any price, safety first instead of duty first, the love of soft living and the get rich quick theory of life." -Theodore Roosevelt
Reply:Yes but.. I bought an AC/DC clamp on ammeter for exactly that purpose.  It turns out that my DC circuit won't register correctly.. I suspect the output in DC mode is really a sine wave sent thru a rectifier bridge.. The AC output registers fine. (Old Century AC/DC buzz box stick welder.)   Because the clamp is supposed to be centered about the cable, I've always been forced to use two people to take a reading. Me welding, wife holding the meter.  I am able to calibrate the AC portion of the output, and from that calculate the DC output (using the painted dial indicator on the face of the machine.) My machine outputs 95 amps actual when the dial reads 125 amps.--zip
Reply:If you are worried about bad connections, that shows up as a voltage drop that is excessive.  You would have to run some current through the circuit, and measure the voltage between the welder and the stinger, the welder and the ground clamp, and many other points.I would probably do that by turning the current down low and then shorting the stinger and the ground cable.   (Assuming that you have a constant current welder, like one would use on stick or TIG).  Low current should protect you from overheating anything, and then you can chase voltages without a pesky arc to make the measurements troublesome.   Would I leave it shorted for 30 minutes?  No, but in 5 minutes I should be able to take all the voltage measurements that I needed.  I doubt if it matters if you use AC or DC, or digital or analog voltmeter, as long as the voltmeter will measure fractions of a volt.  I would probably grab my digital voltmeter, since the current and voltage should be stable; if I was trying to measure this while someone was welding, I would look for an analog meter.You have to put a load on the system, current through the wires, to find the bad connections.  Open circuit voltages will never let you find the bad connections, until they go completely open.Measuring amps is a different question than trying to find poor connections.My two cents.RichardSculptures in copper and other metalshttp://www.fergusonsculpture.comSyncrowave 200 Millermatic 211Readywelder spoolgunHypertherm 600 plasma cutterThermal Arc GMS300 Victor OA torchHomemade Blacksmith propane forge
Reply:Go to your local weld service station.I'm certain they'd be quite happy to hook up your machine to a load bank and let you know how close you are to the dial settings.CWI, CWE, CST for Miller, Lincoln, Thermadyne, Hypertherm & ESABMillermatic 350PLincoln Invertec 205 AC/DCVictor combo torchESAB PCM 1125
Reply:Originally Posted by rafergusonIf you are worried about bad connections, that shows up as a voltage drop that is excessive. Richard
Reply:Excessive voltage across a connection will cause it to become hot. That being the case, you may see burns at junctions or under load detect the heat.
Reply:As Maedar says, load testing is always a valid test and option and is simply "shorting the machine out". There's nothing wrong with "shorting a machine out" in a controlled fashion. Keeping duty the cycle at various ranges in mind, and of course the cumulative effects of internal heat build up during extended testing. As a side note, the heat that is generated at resistance joints is a result of power losses of which current is a major player. The heat is not a product of voltage drop alone. There will be a current loss also."The things that will destroy America are prosperity at any price, peace at any price, safety first instead of duty first, the love of soft living and the get rich quick theory of life." -Theodore Roosevelt
Reply:I had a similar problem a few years back.AC current can be measured most easily with a clamp meter - cheap these days at $10 - $40.For DC current I had a challenge because my clamp meter was AC only.I went another route but you have to know the gauge of your welding wire.Use a wire look up table (on the web now) to find the resistance of your gauge of wire.Here's an example - Measuring the DC current:I was using #1 gauge copper cables. According to the charts, the resistance R of #1 gauge copper wire is 0.1264 ohms per 1000 feet. That means that 9.91 feet of wire has a resistance of 0.00100 ohms.Recall Voltage V = Current I x Resistance R.If we pass 1 amp through that resistance (0.00100 ohms), we will create a voltage drop of 0.001 volt (1 millivolt).A welding a current of 100 amps in that cable will create 100 millivolts on a voltmeter.Thus, we can read millivolts just as if it was amps of current.I connected the leads from a digital voltmeter into the #1 gauge ground cable at two points 9.91 feet (~9 ft 11 inches) apart – just pushed the needle-like tips into the cable.I too found that I could not weld and read the voltmeter at the same time… so after exhausting my wife, I just used a digital camera set to movie mode to record the meter readings while I welded - that worked well.Maybe that will help,Rick V